To persuade someone to comply with your request, use specific details, not vague statistics. Vivid description enables people to “see.”

Your point is more compelling when you present the audience with information that has imagery, because people can visualize the benefits or consequences. Bland narrative has little impact.

In a study at Johns Hopkins, researchers thought that most consumers can’t comprehend calorie counts, so “250 calories” beside a menu item doesn’t mean anything to the customer. So they posted a sign on the menu boards at nearly two dozen Taco Bell restaurants in the Baltimore area. The signs said how many miles a person would need to walk or run to work off the calories contained in the sugary drinks. The sign said a 20-ounce soda would require 5 miles of walking or 50 minutes of running for a 110-pound person to burn off the calories.

Sara Bleich, a professor of health policy and management, who was among the researchers who sat in the back and watched adolescents read the sign, said the calorie information and the amount of exercise necessary to work it off influenced what they bought.

Many kids also started buying smaller drinks. Before the signs were posted, more than 50 percent of the teens who came in bought drinks 16 ounces or larger. After reading the signs, purchases of large-size beverages dropped to 37 percent.

Psychologists used the same tactic in a California energy-saving experiment, when residents were not enrolling in a conservation program in high numbers. Psychologists Marti Gonzales and Elliot Aronson trained energy auditors to go house to house and present a more vivid appeal when they tried to persuade residents to participate in the program.

“If you were to add up all the cracks around and under the doors of your home, you’d have the equivalent of a hole the size of a football in your living room wall,” the auditors told homeowners. “Think about all the heat that would escape from a hole that size … And your attic totally lacks insulation. We call that a ‘naked attic.’ It’s as if your attic is facing winter not just without an overcoat but without any clothing at all.”

The results showed that of the people who had heard the more visual presentation, a significantly higher number of residents enrolled in the program than did residents who were approached by psychologists who did not use vivid description.

The reason is that a crack is seen as minor, but a hole the size of a football feels disastrous, Gonzales explained in a social psychology journal. And while people might not know much about insulation, the thought of being naked in the winter focuses a person’s attention and increases the likelihood that the person will take action.